This invention relates to the technical field of printing materials. More particularly, it relates to a printing material suitable for ink jet printers.
Advertising posters have been adhered to windowpanes of buses and trains, windows in buildings, etc. It has been a practice to produce these advertising posters by multi-color printing. Thus, printing materials exclusively for multi-color printing are printed by using ink jet printers to give vivid color images.
When such an advertising poster is adhered to, for example, a windowpane of a bus, it is needless to say that the printed face should be seen from the outside. Moreover, it is favorable that the poster cannot be seen in the bus because of its shielding effect but the sun. can be shining in through it and passengers can look out of the window owing to its light transmission properties.
In FIGS. 4(a) and (b), the numerical symbol 100 stands for an advertising poster of the above-described type wherein an image 107 is formed on a printing material 110.
In this printing material 110, a synthetic paper 102 is adhered to a base material 101 made of a black resin film and a number of holes 106 piercing through the base material 101 and the synthetic paper 102 are formed.
After forming the holes 106 in the printing material 110, an aqueous ink is sprayed onto the synthetic paper 102 with an ink jet printer. When the aqueous ink 105 permeating the synthetic paper 102 is fixed, a desired image 107 is formed.
In a case of using this advertising poster 100, it is adhered to a windowpane from the inside with the synthetic paper 102 having the image formed thereon facing to the window. Thus, the image 107 faces outside so that it can be seen by pedestrians. Although the black base material 101 faces inside, passengers can look out of the window through the holes 106. In this case, the inside of the bus cannot be seen from the outside, since the holes 106 are very small.
Since a desired advertisement can be economically made by using the advertising poster 100, the demand for posters of this type has been increasing in recent years. However, an image printed on the synthetic paper 102 by using an aqueous ink is blurred, which makes the image 107 on the advertising poster 100 of the conventional art unclear.
The present invention, which has been made to overcome the above-mentioned troubles encountering in the prior art, aims at providing a printing material on which a vivid image can be printed by using ink jet printers.
To achieve this object, the printing material according to the present invention consists of a base material made of a resin film, a white layer formed on the base material, and an absorption layer formed on the white layer. The above-mentioned white layer contains titanium oxide and a hydrophilic resin, while the above-mentioned absorption layer contains a water-absorbing resin. Moreover, the base material, the white layer and the absorption layer are provided with a number of holes piercing therethrough.
The term xe2x80x9chydrophilic resinxe2x80x9d means a resin which wets without repelling water (i.e., having no hydrophobic nature) but does not swell with water. Water-soluble resins and water-insoluble ones both fall within the scope of the hydrophilic resin. In the present invention, use can be made of, for example, a polyvinyl resin as this hydrophilic resin.
On the other hand, the term xe2x80x9cwater-absorbing resinxe2x80x9d means a resin which swells with water but is insoluble in water. Owing to these characteristics, an aqueous ink can permeate the water-absorbing resin. In the present invention, use can be made of protein in this water-absorbing resin.
In the present invention, it is advantageous for forming an advertising poster that the base material is a black one.